


A Rather Invasive Check Up (That Is Enjoyable)

by Kitakin



Category: Warhammer 40.000
Genre: "medical check up", 100 per cent consent, Cawl has a crush on Rob, I'm not sure what you are expecting other than a good time, Other, Rob remains oblivious, mechandrites, robo tentacles
Language: English
Status: In-Progress
Published: 2019-09-02
Updated: 2019-09-02
Packaged: 2020-10-05 16:33:58
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 2
Words: 1,985
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/20491865
Author URL: https://archiveofourown.org/users/Kitakin/pseuds/Kitakin
Summary: Roboute Guilliman, Imperial Regent and Primarch of the Ultramarines, does not like having to strip in front of his apothecaries and Victrix guard. Thus Cawl does the honours.





	1. "Prolouge"

**Author's Note:**

> Please forgive the mess (or don't, I really don't care, it's smut). Cawl is referred to as they/them and you can fight me, I know what canon says and I know that I throw canon out the window. 
> 
> Please keep in mind that Cawl has a crush on Roboute because his flesh doesn't need augmenting to be improved and does his best to treat Cawl with the respect they deserve (and just generally 10,000+ years of pining because they were noticed for their talent and encouraged to continue).

Cawl does mechandrite things to Roboute and his guard to give them check ups.

Grumpy Roboute as marines try to remove the last bits of clothing for the check up? Roboute, refusing to go to check up because that involves losing his underwear and he finds his scars a little bit embarrassing and as the absolute superior officer it's most improper. Roboute being "No I cannot be the loss of their delightful innocence." Because only the naïve ones can tolerate being around him naked without staring, Cato has been banned from all check-ups because he keeps on having to have the happy grin punched off his face.

Roboute being oblivious to Cawl's crush even though all Techmarines can see it? Cawl politely invites him for a check up in wherever they have their base. Roboute begrudgingly goes.

[Please keep in mind that Cawl has a crush on Roboute because his flesh doesn't need augmenting to be improved and does his best to treat Cawl with the respect they deserve (and just generally 10,000+ years of pining because they were noticed for their talent and encouraged to continue).]


	2. BEGIN THE SIN!

**Summary for the Chapter:**

> Smut happens here. Take everything as literally as possible when it comes to the mechandrites and slippery probes.

**Notes for the Chapter:**

> You had your appetizer, now for the main dish.

Roboute arrives in full armour, because that usually gets him out of health check up which involve the apothecaries and guards and Cawl is the only one that can get it off with speed.

Roboute shivers when the cool mechandrites touch bare skin. Naked save for stretchfab underwear, it left little to the imagination. 

"Last check ups, failure to attend. This requires intensive investigation of body. Are you ready Imperial Regent?"

"Cawl. When in private we can use each others names. Titles can be left to the side." 

Mechandrites hover over the elastic, patiently waiting for the primarch to remove the last item of clothing.

Roboute huffs and digs a thumb beneath the fabric, pulling it off with efficiency and then standing straight again. Hands carefully placed above his privates in a show of modesty as his ears started to turn pink. 

The mechandrites stole away the offending bit of cloth. Neatly folded away in some corner to have all the DNA extracted for later. Warming quickly, more mechandrites joined in the patient hovering over the primarch's form. Once optimal temperature was reached, the metal limbs slid around his torso, under his arms and legs, taking the weight away from him.

Some very thin mechandrites supporting head and neck, careful to not irritate the area where the scar had been removed.

Cawl carefully lifted the primarch up so that the scanners could take their measurements, Roboute always found this to be a rather vulnerable position. Legs bent gently open, arms wide as fingers and feet were flexed and checked for tension. The head supporting mechandrites gently running through his hair, suspiciously like a hand, soothing the mild anxiousness away.

A low moan escaped as Cawl gently worked tense musculature, working in a rhythm that only they knew would work with maximum effectiveness.

Warm and cool feelers gently tracing over his chest as a scanner blocked his vision to test his eyes. Roboute shivered, trying very hard not to squirm and laugh as he was tickled.

"Requirement: more rest. Heart 1 damage at 1%, heart 2 damage at 0%, lung damage at 5%. Requirement: wear helmet. I know that you don't like it but you have to Roboute." 

Some shame welled into Roboute's cheeks. He felt had gotten weaker, this era was-

"Roboute! I cannot give you a check up if you think thoughts that prevent me from gathering data on all functions!" Interrupted the thought.

More hand like mechandrites stroked down his sides, over his thighs, tickling behind his knees. Roboute kicked and laughed as more joined in the assault upon his skin. Sides, arm pits, stomach, arms, feet. Nothing was left untouched. 

Crying with laughter and bathing in the endorphins, Roboute relaxed. Slowly slumping in the mechandrites strong enough to take titans to pieces.

Now smiling without strain, eyes fluttering as he relaxed and started to drift asleep. Torn out of the doze as a nipple was tweaked, he yelped at the sudden stimulation. 

"I cannot continue to measure your health if you sleep now." Cawl's synthetic voice considerably more human, just for him. 

A little bit of heat welled in his core. The tweak had felt nice. Oh what was he thinking. It always did. "I apologize. I did not intend to fall asleep." He wanted more, but that would be improper.

Cawl resolved the issue for him, Roboute gasped as the tweaked nipple was rolled and sucked at by something. The scanner covering his eyes left everything to the imagination. 

Back arching a little as the sucking increased from gentle to strong. Cawl was probably going to pierce the nipple.

Biting back a noise of discomfort as the deed happened "The other one as well? If you can withstand the pain?" the Imperial Regent heard

"Of course I can. It is nothing." Guilliman frowned, not intending to sound so biting "I am sorry."

"I am not offended. Merely concerned by your lack of care of yourself. And I do not wish to cause more pain than necessary." The voice hiding the movements of the mechandrites coiling around his knees and thighs, legs being suggested to open a little more.

Roboute breathed, Cawl rarely repeated how they got his blood to well exactly where they wanted it. Again the sucking device landed, this time on the other nipple. Less immediate with the piercing. Still Roboute was not fond of the miniscule moment of discomfort.

"Are you alright?" Concern obvious.

"Must my eyes be checked for this length of time? I am sorry. I shouldn't be this averse to pain as little as it is."

"If it causes you pain I require that you tell me this. Otherwise your marines can do this." Cawl used an empty threat.

"I will tell you. But may I please see?"

"You may not find what you see appealing. This would be detrimental to the task you keep on avoiding. Is it unpleasant?"

Roboute squirmed a little and submitted "I am more used to being in control. Surrendering it is... a rare experience as you are probably fully aware. For now it is tolerable." Face burning at the admission.

"If it bothers you please tell me immediately." More mechandrites soothing his hair and chilling the irritated but healing skin.

Roboute gasped quietly. Arching into the sensation, more mechandrites supporting his back, rubbing his sides and chest, thighs and abdomen. Heat began to well again as his buttocks was grabbed and massaged, cheeks pulled gently apart as something slick started to trace long lines of lubricant over the inside of his thighs. Definitely writing words praising his form in ancient Macraggean. For once he did not mind the silent words of worship as his hips were roughly gripped and legs spread wide. Wriggling with anticipation for what would happen next, he grinned.

Another slick and dripping thing joined the other, clearly their intent was to cover his skin with slippery poetry, smaller and larger suction cups began to march over his body as the mechandrites continued to massage and stretch the perfect musculature. "Ah! Cawl!" Roboute squirmed in delight as the suckers worked their way down from his chest, down his abdomen and carefully left their marks on his growing erection and crown jewels.

"Is something wrong?" Cawl stopped everything.

"No!" Roboute shouted as the pleasure stopped. Lowering his voice "I... ah... it feels good. Please continue?" Feeling very bare even though he was surrounded by metal. 

One particularly small sucker attached itself to his head, a small experimental suck elicited a small gasp. The slick probes had completed their task and wrapped themselves around the still growing shaft. Cawl started the massaging again, easing back into the sensations after the abrupt stop. Roboute groaned as all the suckers began again, the slick things working their way around each, swirling over the sensitive skin. Surrendering to the sensation and smiling as the mechandrites behind his head rubbed behind his ears "This feels very good."

A happy little beep sounded nearby. "Thank you Roboute. It is supposed to."

The primarch released a moan as the slick things worked their way slowly up and down his shaft. Suckers never staying in the same place. Mechandrites clawed down his sides. More slick things joining the ones on his cock, massaging his balls, travelling down to his arse. 

"Are you ready Roboute?" 

"Yes Belisarius."

One slick thing wriggled its way inside of him. Causing Roboute to laugh with how it tickled. It was too small to hurt let alone stretch anything. The primarch writhed. For him it was on the border of over stimulation. "Ah! B-Bel!" He gasped, voice breaking as his prostate was found with extreme efficiency. The slick probe pulsed. Thickening, stretching him. "BEL!" A well lubricated probe had started to vibrate against his frenulum. Hips bucking from the unusual feeling. The vibrating stopped. Roboute whined. The vibrating continued. Roboute shouted again and squirmed. The vibration's intensity was lowered. Roboute was gasping a groan. The mechandrites in his hair rubbing soothing circles as others started to play with his nipples. "Beeelll." He whined once more. Moving his hips as much as he could in tandem with the pulsing and swirling tentacles. "Bel? Please?" The mechandrites holding his hips in place loosened a little. 

Roboute moved more the instant he could. Riding the now far thicker probe as it continued to pulse and test his prostate. Moaning as a few suction cups left their marks on his neck. "Please Bel. More?" 

The slick things working his cock picked up their pace, vibrating, pulsing. Guilliman yelled. It felt so so so good. Moving with their movement, feeling so wonderfully full. Thrusting faster, more desperately. "Ah! Bel! You aarrhhh! MMnpf!" The probe on his prostate pushed into the sensitive spot. Roboute's self discipline broke down as he came, screaming. His vision going white.

"Roboute?" The primarch slowly came to, panting as the last of his cum was sucked out. Limp and bathing in the after glow, the mechandrites slowly uncoiled from their firm hold, cradling him. A cool hand gently touched his. Everything was tingling with sensitivity, still he held the far smaller one. "I am alright Belisarius." Still blind due to the scanner blocking his vision, Roboute kept his eyes closed "I am alright." Another hand gently caressed his face, leaning into the touch "Thank you for your immense patience with me." Sighing contentedly.

"I do not mind. If my procedures are less stressful for you, then that is a compliment to my understanding of your physiology... as mystifying as it is." 

"Mystifying? How so?" He turned to the source of the voice.

The scanner above his eyes slowly removing itself. Cawl's regrown upper body augmented with a millipede-esque lower body. Flat, steel grey eyes carefully observing the Primarch's stormy blue. Waiting for something.

"I have not seen your flesh face in over 500 years. To think that 10,000 have passed from your perspective." Reality crashing on Roboute's head.

"Mystifying because you have more nerves for pleasure in areas that tend to have fewer." Their face turning to a frown as the Regent's stress levels started to rise again. "Eat." Belisarius held out a tube for Guilliman to suck on. 

Without complaint he did as he was told, eyebrows rising to his hair line as his mouth was filled with a mint-mango smoothie. "Where you find the space for farms I do not know and dare not question. This is delicious." It tasted freshly made. 

"I have my sources." Cawl murmured quietly. 

Once satisfied, Roboute yawned. The company, the cradling, the food. All the more reason to rest for a short while...

Belisarius Cawl smiled. The remaining tests could be done without any invasion. How peacefully the overworked man could sleep in their arms.


End file.
